Yokohama pneumatic rubber fender shall consist of an out rubber&comma; reinforcement synthetic-tyre-cord layer&comma; and inner rubber&comma; vulcanized firmly&period; The out rubber are used to protect the cord layers and inner rubber from abrasion and other external forces&period; This rubber compound have sufficient tensile and tear resistance strength to withstand anticipated weather conditions and severe usage&period; The reinforcement synthetic-tyre-cord layer strong enough to maintain the internal air pressure of the fender&period; The inner rubber layer seals the pressurized air inside the fenderFenders of diameter 2500mm and larger equipped with safety valve for releasing excess internal pressure when the fenders are over-compressed accidentally&period;